Observations on Terra del Fuego. 407 



ma for thirty-seven successive days was 65°, and the thermometer on 

 some of the days rose to 60° ; yet there were no Orthoptera, very few 

 Diptera, Lepidoptera, or Hymenoptera. In the pools of water I found 

 but few aquatic beetles, and not any fresh-water shells. Succinea at 

 first appears an exception ; but here it must be called a terrestrial species, 

 for it lives on the damp herbage far from water. Land-shells could only 

 be procured in the same situations with the alpine beetles. I have al- 

 ready contrasted the climate, as well as the general appearance of Terra 

 del Fuego with that of Patagonia, and the difference is strongly exem- 

 plified in the entomology. I do not believe that they have a species in 

 common ; certainly the general character of the insects is widely diffe- 

 rent. If we turn from the land to the sea, we shall find the latter as 

 abundantly stocked with living creatures as the former is poorly so. In 

 all parts of the world a rocky and partially protected shore perhaps sup- 

 ports, in a given space, a greater number of individual animals than any 

 other kind of station. Here, under every stone, numerous crawling crea- 

 tures swarmed, and especially Crustacea of the family of Cymothoades. 

 The number of Sphaeroma was truly wonderful : as these animals, when 

 coiled up, have some resemblance to Trilobites, they were an interesting 

 sight to a geologist. On the tidal rocks patelliform shells of large size 

 were very abundant. Even at the depth of forty or fifty fathoms, the 

 bottom of the sea was far from steril, as was shewn by the abundance 

 of small strong corallines. 



Aquatic Forests of the Southern Hemisphere. — There is a marine produc- 

 tion, which from its importance is worthy of a particular history. It is 

 the kelp or Fucus giganteus of Solander. This plant grows on every 

 rock from low-water mark to a great depth, both on the outer coast 

 and within the channels. I believe, during the voyages of the Adven- 

 ture and Beagle, not one rock near the surface was discovered which was 

 not buoyed by this floating weed. The good service it thus affords to 

 vessels navigating near this stormy land is evident ; and it certainly has 

 saved many a one from being wrecked. I know few things more 

 surprising than to see this plant growing and flourishing amidst those 

 great breakers of the western ocean, which no mass of rock, let it be ever 

 so hard, can long resist. The stem is round, slim}-, and smooth, and 

 seldom has a diameter of so much as an inch. A few taken together are 

 sufficiently strong to support the weight of the large loose stones to 

 which in the inland channels they grow attached ; and some of these 

 stones arc so heavy, that when drawn to the surface they can scarcely be 

 lifted into a boat by one person. 



Captain Cook, in his second voyage, says, that at Kerguelen Land, 

 " some of this weed is of a most enormous length, though the stem is not 

 much thicker than a man's thumb. I have mentioned, that on some of 

 the shoals upon which it grows, wo did not strike ground with a line of 

 twenty-four fathoms. Tho depth of water, therefore, must have been 



